Midrash su Levitico 10:12

1) (Vayikra 10:12): "And Moses spoke to Aaron and to Elazar and Ithamar his sons": His sons were equal to him in (deserving) honor and they were equal to him in keeping silent (viz. Vayikra 10:3). I might think that his first sons, too, (Nadav and Avihu) were equal to him in honor. It is, therefore, written (of Elazar and Ithamar) "his remaining sons." His remaining sons were equal to him in honor, but not the first ones.

2) R. Shimon b. Gamliel said in the name of R. Elazar b. Azaryah: It is written (Bamidbar 3:4): "And Nadav and Avihu died before the L–rd in offering a strange fire before the L–rd in the desert of Sinai; and they did not have sons. And Elazar and Ithamar officiated as priests in the presence of Aaron their father." For if they did have sons, they would have taken precedence to Elazar and Ithamar. For all who take precedence in inheritance take precedence in (assuming a position of) honor. If so, why is it written "his remaining sons"? Moses said to them: Should you not observe (i.e., imprint upon your minds) what happened to these (Nadav and Avihu) because they did not take counsel (see Miluim Shemini 32) and they were swept away? R. Eliezer says: They were close to being swept away (because of the sin of the golden calf made by Aaron), but the L–rd pitied Aaron (and left a "remnant" for him).

3) (Vayikra 10:12) "Take the meal-offering": This is the meal-offering of Nachshon (viz. Bamidbar 7:12-13). "remaining (from the fire-offerings of the L–rd"): This is the meal-offering of the eighth day (viz. Vayikra 9:4). "from the fire-offerings of the L–rd": They can eat it only after (the sacrifice of) the fire-offerings.